Research On Energy Management Strategy And Power Controller Of Hybrid Fuel Cell Vehicle

Energy crisis and environmental pollution problems need to be solved urgently.As one of the representatives of new energy vehicles,fuel cell vehicles are an ideal solution to replace traditional internal combustion engine vehicles,and are gradually being applied in the transportation industry.Fuel cell vehicles have the advantages of zero emissions,good power performance,high energy conversion rate,and long cruising range.They have attracted great attention from governments of various countries and car companies.In order to realize the efficient and reliable operation of the hybrid fuel cell vehicle power system,and to give full play to the stable and efficient working characteristics of fuel cells and the dynamic adaptability of auxiliary energy sources,it is necessary to select an appropriate energy management strategy to solve the problem of power distribution among multiple energy sources.Therefore,considering the requirements of easy implementation and strong real-time performance in engineering applications,combined with the characteristics of the vehicle's operating mode,three vehicle operation modes have been defined: charging power mode,low power mode and cruise mode,and chooses different energy management strategies for different modes.This paper established a multi-mode hybrid energy management strategy.At the same time,considering the lower-level DC/DC converter controller,an adaptive nonlinear controller based on disturbance observer is designed for external disturbance.Finally,in order to improve the dynamic performance of the fuel cell vehicle motor drive control,an adaptive continuous fast terminal sliding mode control of the drive motor based on a high-order fast terminal sliding mode load torque observer is designed,details as follows:First,select the three-power hybrid topology of fuel cell/battery/supercapacitor and use forward simulation modeling method to model the hybrid fuel cell vehicle.Then,using dynamic analysis,the key parameters of the hybrid power system were matched and designed for the selected vehicle model.Finally,based on the selected topology,a simulation model of the hybrid fuel cell vehicle is built using forward simulation modeling.Secondly,in terms of the energy management strategy design of hybrid fuel cell vehicles,a multi-mode based hybrid energy management strategy was established.Based on the characteristics of the vehicle's operating mode and the significant change in load power of the hybrid fuel cell vehicle,three main modes are defined: charging power mode,low power mode and cruise mode,and After analyzing the operating characteristics of the vehicle in each mode,different energy management strategies are selected for different modes,the improved PI-based energy management strategy is used in the charging power mode,the Charge-Depleting ChargeSustaining energy management strategy is used in the low power mode,and the fuzzy logic parameter turning based single PI energy management strategy is used under the Cruise mode.Then,in terms of the control of hybrid fuel cell vehicle DC/DC converters,a disturbance observer based adaptive nonlinear controller is designed.Based on the ripple rate,the inductor and capacitor of the DC/DC converter is designed,and the state average simulation model and small signal model are established.At the same time,based on the small signal model,the control parameters of the classic PI controller of the DC/DC converter were tuned by using the frequency domain method.Finally,considering the uncertainty and disturbance in the modeling of DC/DC converter system,the nonlinear robust controller for the DC/DC converter of hybrid fuel cell vehicle is designed.In order to further improve the robustness and dynamics of the system,an adaptive nonlinear controller based on disturbance observer is designed.Finally,in terms of the control of hybrid fuel cell vehicle drive motor,a high-order fast terminal sliding mode load torque observer based adaptive continuous fast terminal sliding mode controller is designed.After analyzing the existing automobile drive motors from the perspective of performance and market,the permanent magnet synchronous motor is used as the hybrid fuel cell vehicle drive motor in this paper.Then,based on the mathematical model of permanent magnet synchronous motor,the control parameters of the permanent magnet synchronous motor traditional PI controller are adjusted using the idea of active power and internal model.At the same time,considering the disturbance of the motor system during the driving of the vehicle,an adaptive continuous fast terminal sliding mode drive controller is designed,and in order to improve its anti-load disturbance performance,it is compensated with a high-order fast terminal sliding mode load torque observer.